I don’t have one, but they are very easily DIY upgradable. The sensor chip is the same as is in many Arduino and the chip that talks with wifi/ewelink is separate.
I am waiting for one and was going to add a microwave sensor and LED strip; what I haven’t found is instructions on how the two chips talk to each other. Itead provide open firmware code for the main chip so it should be easily obtained from reading that. You’d probably have to pretend the CO2 sensor was something else, like air quality.
I don’t have a specific CO2 sensor, but have an organic gas one. I would guess the actual chip would cost £2-3 from a Chinese Internet shop. If itead were more open about the communication then someone would have already written the CO2 sensor firmware and you could spend about 1 minute customising it for your purpose.
From what I’ve read most people are changing both chip’s firmware and unlinking it from ewelink. Seems rather unnecessary.
about 1 month ago
Essentially, my argument is there are loads of potential specialist uses for a wifi/cloud connected sensor device and with two discrete chips connected by a simple connection they should do more to facilitate people being to add on whatever sensor they want.
There is another thread about a wind/rain sensor - no reason this couldn’t also be added as a remote waterproof sensor.